Scrotal filariasis

　　1. Etiology

　　Scrotal filariasis is a disease caused by early or late lymphatic damage of the male reproductive system due to Wuchereria bancrofti. Scrotal filariasis is caused by the residence of filarial worms in the lymphatic vessels and lymph nodes of the inguinal region and scrotum spermatic cord.

　　2. Pathogenesis

　　The adult filarial worms parasitize in the lymphatic system, causing mechanical injury and allergic inflammatory reactions, resulting in damage to the walls of the lymphatic vessels near the chyle pool, the lumbar intestinal trunk, central lymphatic vessels, and lymphatic trunks, especially the valves, leading to the tortuosity and dilation of lymphatic vessels, and incomplete closure of the valves. The flow of chyle lymph fluid is slow and retained, increasing the pressure inside the vessels, causing the fluid to reflux and accumulate in the distal管道. Over time, this leads to relative incomplete closure of the distal lymphatic valves and varicose veins. Half of the patients infected with filarial worms do not show symptoms but have microfilariae in the blood, becoming 'asymptomatic carriers'. Malayan filarial worms mainly parasitize in the superficial lymphatic system, which can cause lymphadenitis or lymphangitis of the extremities, lower limb lymphedema or rubber swelling, and generally no damage to the urinary and reproductive systems. Bancroftian filarial worms, in addition to parasitizing in the lymphatic system of the extremities, can also parasitize in the deep lymphatic system, such as the peritoneum and lymphatic tissue near the spermatic cord, so deep symptoms such as chyluria and inflammation and nodules in the spermatic cord, epididymis, testis, and scrotum are more common.

　　This disease often complicates with epididymitis, and occasionally orchitis. In the acute phase, recurrent lymphangitis, lymphadenitis, and fever can occur, and in the chronic phase, lymphedema and elephantiasis may appear. Severe cases may present with myocarditis, edema of the lower limbs or scrotum, mental symptoms, and even exhaustion. Therefore, once the infection of filariasis is diagnosed, it is necessary to undergo active anti-infection treatment to reduce complications, such as using diethylcarbamazine 200mg, 3 times a day, for 7 consecutive days, with a total dose of 4.2g (for adults).

　　1. Medical History

　　History of residence in the filariasis area, with a history of filariasis.

　　2. Clinical Manifestations

　　1. Acute Spermatic Oophoritis:

　　It can cause severe local pain, radiating to the lower abdomen and腰部; or it may be mild, only dull pain and a pulling sensation. Physical examination may show swelling, hardening, and diffuse thickening of the spermatic cord, with nodules that are not related to the vas deferens, mostly located at the lower end of the spermatic cord and the tail of the epididymis, with mild fever.

　　2. Spermatic Cord Lymphangitis:

　　It is common after repeated attacks of orchitis, with the spermatic cord thickened, tortuous, dilated, forming a bead-like appearance, or bundled into thick strands, worsening during activity and standing, and improving during rest and lying down. Occasionally, lymphatic vessels may dilate into a cyst-like shape, containing white or pale yellow turbid fluid with soft texture.

　　3. Hydrocele and Chylous Hydrocele of the Tunica Vaginalis:

　　It is a common complication of filariasis. Initially, the effusion is less, and due to recurrent attacks of orchitis and epididymitis, the amount of fluid increases, reaching hundreds of milliliters, which can cause the penis to shrink into the scrotum. The effusion in the early stage is straw yellow and clear; in the late stage, the lymphatic vessels of the tunica vaginalis become varicose and rupture, and chyle is poured into the tunica vaginalis sac, known as chylous hydrocele. The effusion is milky white and often contains microfilariae. In the late stage, the tunica vaginalis becomes thickened and fibrotic plaques are produced, the testicle is compressed and atrophied. The transparency test is positive in the early stage and may be negative when the tunica vaginalis wall is thickened and chyle is present.

　　3. Experimental Treatment

　　After treatment with diethylcarbamazine and carbarsone, new granulomatous nodules often appear in the spermatic cord and epididymis, and the original granulomatous nodules cannot regress.

　　1. Prevention and Elimination of Mosquitoes

　　Cut off the pathways of transmission and eliminate the breeding places of mosquitoes. It is best to use mosquito nets during the season with many mosquitoes; when working outdoors, pay attention to applying mosquito repellent oil, mosquito repellent, and other repellents to the exposed parts of the skin, and the head can be protected with a mosquito net made from cotton dipped in 701 mosquito repellent oil.

　　2. General Survey and General Treatment

　　Conduct a general survey of the population over 1 year old in the epidemic areas during the summer, requiring more than 95% of residents to accept blood collection; discover patients and carriers early, provide timely treatment, ensuring people's health and reducing and eliminating the source of infection. In winter, carry out general treatment for those with microfilaria-positive or those with a history and signs of filariasis but microfilaria-negative.

　　3. Epidemiological Monitoring

　　Strengthen the epidemiological monitoring in areas that have reached the basic criteria for the elimination of filariasis. In the monitoring work, attention should be paid to:

　　Re-examine and re-treat original positive patients; conduct supplementary examination and treatment for those who have not been tested in the past; at the same time, strengthen the management of floating population, discover patients in a timely manner, and provide treatment until they become negative.

　　Strengthen the mosquito vector monitoring of blood test positive households, and upon finding infected mosquitoes, expand blood testing and mosquito control around the infected household to clear the epidemic focus and prevent further transmission.

　　Four, protect susceptible populations

　　In endemic areas, diethylcarbamazine salt therapy is used, 3g of diethylcarbamazine is mixed into 1 kilogram of salt, an average of 16.7g of salt per person per day, containing 50mg of diethylcarbamazine, taken for half a year, can reduce the positive rate of microfilaria in the population.

　　1. Increase in eosinophils in peripheral blood, microfilaria can be found in venous blood at night.

　　2. Biopsy of the spermatic cord, epididymal nodules can confirm filariasis, and adult filariae can be picked out from the section.

　　3. Microfilaria examination in body fluids and urine: Microfilaria can also be found in various body fluids and urine, so microfilaria can be found in hydrocele, lymph, ascites, chyluria, and urine, etc. The above-mentioned body fluids can be directly smeared, stained, and examined under a microscope; or centrifugal concentration method, thin film filtration concentration method, and other examination methods can be used. Add ether to the chylous fluid to fully dissolve the fat, remove the fat layer on the surface, dilute it with water 10 times, and centrifuge at 1500-2000 rpm for 3-5 minutes, and then examine the sediment under a microscope.

　　4. For patients with negative microfilaria in blood, biopsy of subcutaneous nodules, superficial lymph nodes, and epididymal nodules can be performed to confirm the diagnosis.

　　1. Foods that are good for scrotal filariasis patients:

　　Maintain a light diet, eat more fresh vegetables and fruits such as bananas, strawberries, apples, etc. Because they are rich in nutrients, eating more immune-boosting foods such as propolis can improve immunity. In this way, enhance personal disease resistance. In daily life, it is also necessary to reasonably match the diet and pay attention to adequate nutrition.

　　2. Foods that should not be eaten for scrotal filariasis:

　　Do not eat or eat less spicy and pungent foods.

　　Treatment:

　　1. Appropriate rest, use scrotal support when walking.

　　2. For patients found to have microfilaria in the blood, antifilarial drug treatment can be given.

　　3. For patients with severe varicocele of spermatic cord, surgical excision can be performed. The nodules of recurrent acute epididymitis can also be surgically excised.

　　4. For patients with hydrocele of spermatic cord, surgical excision or inversion can be performed.